"onyxx" writes:
Hello, i am working on a 15 inch color monitor. I have a 150W light
bulb connected and when i turn the monitor on, it starts to pulsate for
about 10 seconds at 2hz(+-)So it pulsates like 15 to 20 times and then
it stays at normal brightness. During all of this the monitor is NOT
connected to a PC, but when i do it statrs to pusate again but this
time indefenetly. Iīve tried changing the refresh rate and this causes
the pulses to speed up, so if i go from 800x600/50hz to 800x600/60hz,
the pulsating goes from about 1hz to 2hz and if I pull the VGA
connector the pulsating stops. Should i try a bigger light bulb?
I also get over 1000Vdc (DMM goes blank)both at the chopper
transistorīs and HOTīs drain pin. What controls B+ voltage? is it
just the HOT or is there a voltage regulator somewhere?
I am looking for a bad V regulatro or maybe a bad resistor somewhere,
Am I in the right direction here?
What were the original symptoms?
100 W may be a bit low for a 15 inch monitor to come up properly with a
signal.
P.S. Don't put your poor DMM on those terminals! If it does come up
properly, the DMM may not survive.
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